Assessment of TNF-α, IL-12/23, and IL-17 in Psoriasis: Only TNF-α Reflects Clinical Response After 12 Weeks of Biologic Treatment.

BACKGROUND: Tumor necrosis factor-alpha (TNF-α), IL-12/23, IL-17A, and IL-17F are key proinflammatory cytokines involved in the pathogenesis of psoriasis. Biologic therapies targeting these interleukins have demonstrated clinical efficacy. However, the exact relationship between their serum levels and clinical response remains unclear. The aims of this study are to assess changes in cytokine levels (TNF-α, IL-12/23, IL-17A, IL-17F) after 12 weeks of biologic treatment in psoriasis to test if there is any correlation between their serum level and PASI (Psoriasis Area Severity Index) and DLQI (Dermatology Life Quality Index) scores before or after treatment and to check the influence of clinical and lifestyle factors on these levels. METHODS: In this prospective study, 36 patients with moderate-to-severe plaque psoriasis receiving anti-TNF-α, anti-IL-17, or anti-IL-23 therapy were assessed at baseline and after 12 weeks. The serum levels of these cytokines were measured using the ELISA technique. Clinical response was evaluated using PASI and DLQI scores. Spearman correlation analysis was used to assess the relationship between interleukins' serum levels and these scores. RESULTS: A significant decrease in TNF-α levels and DLQI and PASI scores was observed after 12 weeks across all treatments. A moderate positive correlation (r = 0.391, p = 0.018) was found between serum TNF-α levels and PASI scores at week 12. CONCLUSIONS: The serum levels of TNF-α are significantly correlated with PASI scores following 12 weeks of biologic therapy, supporting their potential role as a biomarker for monitoring treatment efficacy in psoriasis.